Drugs from the deep: scientists explore ocean frontiers

Some send divers in speed boats, others dispatch submersible robots to search the seafloor, and one team deploys a "mud missile" -- all tools used by scientists to scour the world's oceans for the next potent cancer treatment or antibiotic. A medicinal molecule could be found in microbes scooped up in sediment, be produced by porous sponges or sea squirts -- barrel-bodied creatures that cling to rocks or the undersides of boats -- or by bacteria living symbiotically in a snail. But once a compound reveals potential for the treatment of, say, Alzheimer's or epilepsy, developing it into a drug typically takes a decade or more, and costs hundreds of millions of dollars. "Suppose you want to cure cancer -- how do you know what to study?" said William Fenical, a professor at Scripps Institution of Oceanography, considered a pioneer in the hunt for marine-derived medicines. "You don't." With tight budgets and little support from big pharma, scientists often piggyback on other research expeditions. Marcel Jaspars of Scotland's University of Aberdeen said colleagues collect samples by dropping a large metal tube on a 5,000 metres (16,400 feet) cable that "rams" the seafloor. A more sophisticated method uses small,remotely operated underwater vehicles. "I say to people, all I really want is a tube of mud," he told AFP. This small but innovative area of marine exploration is in the spotlight at crucial UN high seas treaty negotiations, covering waters beyond national jurisdiction, which could wrap up this week with new rules governing marine protected areas crucial for protecting biodiversity. Nations have long tussled over how to share benefits from marine genetic resources in the open ocean -- including compounds used in medicines, bioplastics and food stabilisers, said Daniel Kachelriess, a High Seas Alliance co-lead on the issue at the negotiations. And yet only a small number of products with marine genetic resources find their way onto the market, with just seven recorded in 2019, he said. The value of potential royalties has been estimated at $10 million to $30 million a year. - New frontiers - That long pipeline is no surprise to Carmen Cuevas Marchante, head of research and development at the Spanish biotech firm PharmaMar. For their first drug, they started out by cultivating and collecting some 300 tonnes of the bulbous sea squirt. From one tonne we could isolate less than one gram" of the compound they needed for clinical trials, she told AFP. The company now has three cancer drugs approved, all derived from sea squirts, and has fine-tuned its methods for making synthetic versions of natural compounds. Even if everything goes right, Marchante said, it can take 15 years between discovery and having a product to market. Overall, there have been 17 marine-derived drugs approved to treat human disease since 1969, with some 40 in various stages of clinical trials around the world, according to the online tracker Marine Drug Pipeline. Those already on the market include a herpes antiviral from a sponge and a powerful pain drug from a cone snail, but most treat cancer. That, experts say, is partly because the huge costs of clinical trials -- potentially topping a billion dollars -- favours the development of more expensive drugs. But there is a "myriad" of early-stage research on marine-derived compounds for anything from malaria to tuberculosis, said Alejandro Mayer, a pharmacology professor at Illinois' Midwestern University who runs the Marine Pipeline project and whose own speciality is the brain's immune system. That means there is still huge potential to find the next antibiotic or HIV therapy, scientists say. It might be produced by a creature buried in ocean sediment or quietly clinging to a boat's hull. Or it could be already in our possession: laboratories around the world hold libraries of compounds that can be tested against new diseases. "There's a whole new frontier out there," said Fenical. (Source AFP)